Technologies of high-definition media interface (HDMI) or high definition displayport (DP) has advantages of non-compression lossless high resolution display characteristics and real-time performance to bring high quality audio-visual experience to users. A HDMI or DP based keyboard, video, mouse (KVM) system is a common comprehensive system that provides users with controllable high-definition video display services.
The high-definition images without compression require a high data rate, which limits the application of this technology. Since a high-definition signal is attenuated exponentially in a cable, a high-definition HDMI or DP signal, especially a high-definition 4k or 8k signal, can only be transmitted a few meters away even with an expensive wire, thus greatly limiting applications of non-compression lossless high-definition display based on the HDMI or DP.
Due to the limitation of transmission distance of high-definition data, a KVM system can only provide the high-definition video display services in a small range. Therefore, an effective signal extension circuit system is required to extend a transmission distance of a high-definition signal.